#!/usr/bin/env python
# Copyright (c) 2012 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

'''python %prog [options] platform chromium_os_flag template

platform specifies which platform source is being generated for
  and can be one of (win, mac, linux)
chromium_os_flag should be 1 if this is a Chromium OS build
template is the path to a .json policy template file.'''

from __future__ import with_statement
from collections import OrderedDict
from functools import partial
import json
from optparse import OptionParser
import re
import sys
import textwrap
import types
from xml.sax.saxutils import escape as xml_escape


CHROME_POLICY_KEY = 'SOFTWARE\\\\Policies\\\\Google\\\\Chrome'
CHROMIUM_POLICY_KEY = 'SOFTWARE\\\\Policies\\\\Chromium'


class PolicyDetails:
  """Parses a policy template and caches all its details."""

  # Maps policy types to a tuple with 4 other types:
  # - the equivalent base::Value::Type or 'TYPE_EXTERNAL' if the policy
  #   references external data
  # - the equivalent Protobuf field type
  # - the name of one of the protobufs for shared policy types
  # - the equivalent type in Android's App Restriction Schema
  # TODO(joaodasilva): refactor the 'dict' type into a more generic 'json' type
  # that can also be used to represent lists of other JSON objects.
  TYPE_MAP = {
    'dict':             ('TYPE_DICTIONARY',   'string',       'String',
                        'string'),
    'external':         ('TYPE_EXTERNAL',     'string',       'String',
                        'invalid'),
    'int':              ('TYPE_INTEGER',      'int64',        'Integer',
                        'integer'),
    'int-enum':         ('TYPE_INTEGER',      'int64',        'Integer',
                        'choice'),
    'list':             ('TYPE_LIST',         'StringList',   'StringList',
                        'string'),
    'main':             ('TYPE_BOOLEAN',      'bool',         'Boolean',
                        'bool'),
    'string':           ('TYPE_STRING',       'string',       'String',
                        'string'),
    'string-enum':      ('TYPE_STRING',       'string',       'String',
                        'choice'),
    'string-enum-list': ('TYPE_LIST',         'StringList',   'StringList',
                        'multi-select'),
  }

  class EnumItem:
    def __init__(self, item):
      self.caption = PolicyDetails._RemovePlaceholders(item['caption'])
      self.value = item['value']

  def __init__(self, policy, chrome_major_version, os, is_chromium_os,
               valid_tags):
    self.id = policy['id']
    self.name = policy['name']
    self.tags = policy.get('tags', None)
    self._CheckTagsValidity(valid_tags)
    features = policy.get('features', {})
    self.can_be_recommended = features.get('can_be_recommended', False)
    self.can_be_mandatory = features.get('can_be_mandatory', True)
    self.is_deprecated = policy.get('deprecated', False)
    self.is_device_only = policy.get('device_only', False)
    self.schema = policy.get('schema', {})
    self.has_enterprise_default = 'default_for_enterprise_users' in policy
    if self.has_enterprise_default:
      self.enterprise_default = policy['default_for_enterprise_users']

    expected_platform = 'chrome_os' if is_chromium_os else os.lower()
    self.platforms = []
    for platform, version_range in [ p.split(':')
                                     for p in policy['supported_on'] ]:
      split_result = version_range.split('-')
      if len(split_result) != 2:
        raise RuntimeError('supported_on must have exactly one dash: "%s"' % p)
      (version_min, version_max) = split_result
      if version_min == '':
        raise RuntimeError('supported_on must define a start version: "%s"' % p)

      # Skip if the current Chromium version does not support the policy.
      if (int(version_min) > chrome_major_version or
          version_max != '' and int(version_max) < chrome_major_version):
        continue

      if platform.startswith('chrome.'):
        platform_sub = platform[7:]
        if platform_sub == '*':
          self.platforms.extend(['win', 'mac', 'linux'])
        else:
          self.platforms.append(platform_sub)
      else:
        self.platforms.append(platform)

    self.platforms.sort()
    self.is_supported = expected_platform in self.platforms

    if not PolicyDetails.TYPE_MAP.has_key(policy['type']):
      raise NotImplementedError('Unknown policy type for %s: %s' %
                                (policy['name'], policy['type']))
    self.policy_type, self.protobuf_type, self.policy_protobuf_type, \
        self.restriction_type = PolicyDetails.TYPE_MAP[policy['type']]
    self.schema = policy['schema']

    self.desc = '\n'.join(
        map(str.strip,
            PolicyDetails._RemovePlaceholders(policy['desc']).splitlines()))
    self.caption = PolicyDetails._RemovePlaceholders(policy['caption'])
    self.max_size = policy.get('max_size', 0)

    items = policy.get('items')
    if items is None:
      self.items = None
    else:
      self.items = [ PolicyDetails.EnumItem(entry) for entry in items ]

  PH_PATTERN = re.compile('<ph[^>]*>([^<]*|[^<]*<ex>([^<]*)</ex>[^<]*)</ph>')

  def _CheckTagsValidity(self, valid_tags):
    if self.tags == None:
      raise RuntimeError('Policy ' + self.name + ' has to contain a list of '
                         'tags!\n An empty list is also valid but means '
                         'setting this policy can never harm the user\'s '
                         'privacy or security.\n');
    for tag in self.tags:
      if not tag in valid_tags:
        raise RuntimeError('Invalid Tag:' + tag + '!\n'
                           'Chose a valid tag from \'risk_tag_definitions\' (a '
                           'subproperty of root in policy_templates.json)!')

  # Simplistic grit placeholder stripper.
  @staticmethod
  def _RemovePlaceholders(text):
    result = ''
    pos = 0
    for m in PolicyDetails.PH_PATTERN.finditer(text):
      result += text[pos:m.start(0)]
      result += m.group(2) or m.group(1)
      pos = m.end(0)
    result += text[pos:]
    return result


def ParseVersionFile(version_path):
  major_version = None
  for line in open(version_path, 'r').readlines():
    key, val = line.rstrip('\r\n').split('=', 1)
    if key == 'MAJOR':
      major_version = val
      break
  if major_version is None:
    raise RuntimeError('VERSION file does not contain major version.')
  return int(major_version)


def main():
  parser = OptionParser(usage=__doc__)
  parser.add_option('--pch', '--policy-constants-header', dest='header_path',
                    help='generate header file of policy constants',
                    metavar='FILE')
  parser.add_option('--pcc', '--policy-constants-source', dest='source_path',
                    help='generate source file of policy constants',
                    metavar='FILE')
  parser.add_option('--cpp', '--cloud-policy-protobuf',
                    dest='cloud_policy_proto_path',
                    help='generate cloud policy protobuf file',
                    metavar='FILE')
  parser.add_option('--csp', '--chrome-settings-protobuf',
                    dest='chrome_settings_proto_path',
                    help='generate chrome settings protobuf file',
                    metavar='FILE')
  parser.add_option('--cpd', '--cloud-policy-decoder',
                    dest='cloud_policy_decoder_path',
                    help='generate C++ code decoding the cloud policy protobuf',
                    metavar='FILE')
  parser.add_option('--ard', '--app-restrictions-definition',
                    dest='app_restrictions_path',
                    help='generate an XML file as specified by '
                    'Android\'s App Restriction Schema',
                    metavar='FILE')
  parser.add_option('--rth', '--risk-tag-header',
                    dest='risk_header_path',
                    help='generate header file for policy risk tags',
                    metavar='FILE')
  (opts, args) = parser.parse_args()

  if len(args) != 4:
    print('Please specify path to src/chrome/VERSION, platform, '
          'chromium_os flag and input file as positional parameters.')
    parser.print_help()
    return 2

  version_path = args[0]
  os = args[1]
  is_chromium_os = args[2] == '1'
  template_file_name = args[3]

  major_version = ParseVersionFile(version_path)
  template_file_contents = _LoadJSONFile(template_file_name)
  riskTags = RiskTags(template_file_contents)
  policy_details = [ PolicyDetails(policy, major_version, os, is_chromium_os,
                                   riskTags.GetValidTags())
                     for policy in _Flatten(template_file_contents) ]
  riskTags.ComputeMaxTags(policy_details)
  sorted_policy_details = sorted(policy_details, key=lambda policy: policy.name)

  def GenerateFile(path, writer, sorted=False, xml=False):
    if path:
      with open(path, 'w') as f:
        _OutputGeneratedWarningHeader(f, template_file_name, xml)
        writer(sorted and sorted_policy_details or policy_details,
               os, f, riskTags)

  GenerateFile(opts.header_path, _WritePolicyConstantHeader, sorted=True)
  GenerateFile(opts.source_path, _WritePolicyConstantSource, sorted=True)
  GenerateFile(opts.risk_header_path, _WritePolicyRiskTagHeader)
  GenerateFile(opts.cloud_policy_proto_path, _WriteCloudPolicyProtobuf)
  GenerateFile(opts.chrome_settings_proto_path, _WriteChromeSettingsProtobuf)
  GenerateFile(opts.cloud_policy_decoder_path, _WriteCloudPolicyDecoder)

  if os == 'android':
    GenerateFile(opts.app_restrictions_path, _WriteAppRestrictions, xml=True)

  return 0


#------------------ shared helpers ---------------------------------#

def _OutputGeneratedWarningHeader(f, template_file_path, xml_style):
  left_margin = '//'
  if xml_style:
    left_margin = '    '
    f.write('<?xml version="1.0" encoding="utf-8"?>\n'
            '<!--\n')
  else:
    f.write('//\n')

  f.write(left_margin + ' DO NOT MODIFY THIS FILE DIRECTLY!\n')
  f.write(left_margin + ' IT IS GENERATED BY generate_policy_source.py\n')
  f.write(left_margin + ' FROM ' + template_file_path + '\n')

  if xml_style:
    f.write('-->\n\n')
  else:
    f.write(left_margin + '\n\n')


COMMENT_WRAPPER = textwrap.TextWrapper()
COMMENT_WRAPPER.width = 80
COMMENT_WRAPPER.initial_indent = '// '
COMMENT_WRAPPER.subsequent_indent = '// '
COMMENT_WRAPPER.replace_whitespace = False


# Writes a comment, each line prefixed by // and wrapped to 80 spaces.
def _OutputComment(f, comment):
  for line in comment.splitlines():
    if len(line) == 0:
      f.write('//')
    else:
      f.write(COMMENT_WRAPPER.fill(line))
    f.write('\n')


# Returns an iterator over all the policies in |template_file_contents|.
def _Flatten(template_file_contents):
  for policy in template_file_contents['policy_definitions']:
    if policy['type'] == 'group':
      for sub_policy in policy['policies']:
        yield sub_policy
    else:
      yield policy


def _LoadJSONFile(json_file):
  with open(json_file, 'r') as f:
    text = f.read()
  return eval(text)


#------------------ policy constants header ------------------------#

def _WritePolicyConstantHeader(policies, os, f, riskTags):
  f.write('#ifndef CHROME_COMMON_POLICY_CONSTANTS_H_\n'
          '#define CHROME_COMMON_POLICY_CONSTANTS_H_\n'
          '\n'
          '#include <string>\n'
          '\n'
          '#include "base/values.h"\n'
          '#include "components/policy/core/common/policy_details.h"\n'
          '#include "components/policy/core/common/policy_map.h"\n'
          '\n'
          'namespace policy {\n'
          '\n'
          'namespace internal {\n'
          'struct SchemaData;\n'
          '}\n\n')

  if os == 'win':
    f.write('// The windows registry path where Chrome policy '
            'configuration resides.\n'
            'extern const wchar_t kRegistryChromePolicyKey[];\n')

  f.write('#if defined (OS_CHROMEOS)\n'
          '// Sets default values for enterprise users.\n'
          'void SetEnterpriseUsersDefaults(PolicyMap* policy_map);\n'
          '#endif\n'
          '\n'
          '// Returns the PolicyDetails for |policy| if |policy| is a known\n'
          '// Chrome policy, otherwise returns NULL.\n'
          'const PolicyDetails* GetChromePolicyDetails('
              'const std::string& policy);\n'
          '\n'
          '// Returns the schema data of the Chrome policy schema.\n'
          'const internal::SchemaData* GetChromeSchemaData();\n'
          '\n')
  f.write('// Key names for the policy settings.\n'
          'namespace key {\n\n')
  for policy in policies:
    # TODO(joaodasilva): Include only supported policies in
    # configuration_policy_handler.cc and configuration_policy_handler_list.cc
    # so that these names can be conditional on 'policy.is_supported'.
    # http://crbug.com/223616
    f.write('extern const char k' + policy.name + '[];\n')
  f.write('\n}  // namespace key\n\n'
          '}  // namespace policy\n\n'
          '#endif  // CHROME_COMMON_POLICY_CONSTANTS_H_\n')


#------------------ policy constants source ------------------------#

# A mapping of the simple schema types to base::Value::Types.
SIMPLE_SCHEMA_NAME_MAP = {
  'boolean': 'TYPE_BOOLEAN',
  'integer': 'TYPE_INTEGER',
  'null'   : 'TYPE_NULL',
  'number' : 'TYPE_DOUBLE',
  'string' : 'TYPE_STRING',
}

class SchemaNodesGenerator:
  """Builds the internal structs to represent a JSON schema."""

  def __init__(self, shared_strings):
    """Creates a new generator.

    |shared_strings| is a map of strings to a C expression that evaluates to
    that string at runtime. This mapping can be used to reuse existing string
    constants."""
    self.shared_strings = shared_strings
    self.schema_nodes = []
    self.property_nodes = []
    self.properties_nodes = []
    self.restriction_nodes = []
    self.int_enums = []
    self.string_enums = []
    self.simple_types = {
      'boolean': None,
      'integer': None,
      'null': None,
      'number': None,
      'string': None,
    }
    self.stringlist_type = None
    self.ranges = {}
    self.id_map = {}

  def GetString(self, s):
    if s in self.shared_strings:
      return self.shared_strings[s]
    # Generate JSON escaped string, which is slightly different from desired
    # C/C++ escaped string. Known differences includes unicode escaping format.
    return json.dumps(s)

  def AppendSchema(self, type, extra, comment=''):
    index = len(self.schema_nodes)
    self.schema_nodes.append((type, extra, comment))
    return index

  def AppendRestriction(self, first, second):
    r = (str(first), str(second))
    if not r in self.ranges:
      self.ranges[r] = len(self.restriction_nodes)
      self.restriction_nodes.append(r)
    return self.ranges[r]

  def GetSimpleType(self, name):
    if self.simple_types[name] == None:
      self.simple_types[name] = self.AppendSchema(
          SIMPLE_SCHEMA_NAME_MAP[name],
          -1,
          'simple type: ' + name)
    return self.simple_types[name]

  def GetStringList(self):
    if self.stringlist_type == None:
      self.stringlist_type = self.AppendSchema(
          'TYPE_LIST',
          self.GetSimpleType('string'),
          'simple type: stringlist')
    return self.stringlist_type

  def SchemaHaveRestriction(self, schema):
    return any(keyword in schema for keyword in
        ['minimum', 'maximum', 'enum', 'pattern'])

  def IsConsecutiveInterval(self, seq):
    sortedSeq = sorted(seq)
    return all(sortedSeq[i] + 1 == sortedSeq[i + 1]
               for i in xrange(len(sortedSeq) - 1))

  def GetEnumIntegerType(self, schema, name):
    assert all(type(x) == int for x in schema['enum'])
    possible_values = schema['enum']
    if self.IsConsecutiveInterval(possible_values):
      index = self.AppendRestriction(max(possible_values), min(possible_values))
      return self.AppendSchema('TYPE_INTEGER', index,
          'integer with enumeration restriction (use range instead): %s' % name)
    offset_begin = len(self.int_enums)
    self.int_enums += possible_values
    offset_end = len(self.int_enums)
    return self.AppendSchema('TYPE_INTEGER',
        self.AppendRestriction(offset_begin, offset_end),
        'integer with enumeration restriction: %s' % name)

  def GetEnumStringType(self, schema, name):
    assert all(type(x) == str for x in schema['enum'])
    offset_begin = len(self.string_enums)
    self.string_enums += schema['enum']
    offset_end = len(self.string_enums)
    return self.AppendSchema('TYPE_STRING',
        self.AppendRestriction(offset_begin, offset_end),
        'string with enumeration restriction: %s' % name)

  def GetEnumType(self, schema, name):
    if len(schema['enum']) == 0:
      raise RuntimeError('Empty enumeration in %s' % name)
    elif schema['type'] == 'integer':
      return self.GetEnumIntegerType(schema, name)
    elif schema['type'] == 'string':
      return self.GetEnumStringType(schema, name)
    else:
      raise RuntimeError('Unknown enumeration type in %s' % name)

  def GetPatternType(self, schema, name):
    if schema['type'] != 'string':
      raise RuntimeError('Unknown pattern type in %s' % name)
    pattern = schema['pattern']
    # Try to compile the pattern to validate it, note that the syntax used
    # here might be slightly different from re2.
    # TODO(binjin): Add a python wrapper of re2 and use it here.
    re.compile(pattern)
    index = len(self.string_enums);
    self.string_enums.append(pattern);
    return self.AppendSchema('TYPE_STRING',
        self.AppendRestriction(index, index),
        'string with pattern restriction: %s' % name);

  def GetRangedType(self, schema, name):
    if schema['type'] != 'integer':
      raise RuntimeError('Unknown ranged type in %s' % name)
    min_value_set, max_value_set = False, False
    if 'minimum' in schema:
      min_value = int(schema['minimum'])
      min_value_set = True
    if 'maximum' in schema:
      max_value = int(schema['minimum'])
      max_value_set = True
    if min_value_set and max_value_set and min_value > max_value:
      raise RuntimeError('Invalid ranged type in %s' % name)
    index = self.AppendRestriction(
        str(max_value) if max_value_set else 'INT_MAX',
        str(min_value) if min_value_set else 'INT_MIN')
    return self.AppendSchema('TYPE_INTEGER',
        index,
        'integer with ranged restriction: %s' % name)

  def Generate(self, schema, name):
    """Generates the structs for the given schema.

    |schema|: a valid JSON schema in a dictionary.
    |name|: the name of the current node, for the generated comments."""
    if schema.has_key('$ref'):
      if schema.has_key('id'):
        raise RuntimeError("Schemas with a $ref can't have an id")
      if not isinstance(schema['$ref'], types.StringTypes):
        raise RuntimeError("$ref attribute must be a string")
      return schema['$ref']
    if schema['type'] in self.simple_types:
      if not self.SchemaHaveRestriction(schema):
        # Simple types use shared nodes.
        return self.GetSimpleType(schema['type'])
      elif 'enum' in schema:
        return self.GetEnumType(schema, name)
      elif 'pattern' in schema:
        return self.GetPatternType(schema, name)
      else:
        return self.GetRangedType(schema, name)

    if schema['type'] == 'array':
      # Special case for lists of strings, which is a common policy type.
      # The 'type' may be missing if the schema has a '$ref' attribute.
      if schema['items'].get('type', '') == 'string':
        return self.GetStringList()
      return self.AppendSchema('TYPE_LIST',
          self.GenerateAndCollectID(schema['items'], 'items of ' + name))
    elif schema['type'] == 'object':
      # Reserve an index first, so that dictionaries come before their
      # properties. This makes sure that the root node is the first in the
      # SchemaNodes array.
      index = self.AppendSchema('TYPE_DICTIONARY', -1)

      if 'additionalProperties' in schema:
        additionalProperties = self.GenerateAndCollectID(
            schema['additionalProperties'],
            'additionalProperties of ' + name)
      else:
        additionalProperties = -1

      # Properties must be sorted by name, for the binary search lookup.
      # Note that |properties| must be evaluated immediately, so that all the
      # recursive calls to Generate() append the necessary child nodes; if
      # |properties| were a generator then this wouldn't work.
      sorted_properties = sorted(schema.get('properties', {}).items())
      properties = [
          (self.GetString(key), self.GenerateAndCollectID(subschema, key))
          for key, subschema in sorted_properties ]

      pattern_properties = []
      for pattern, subschema in schema.get('patternProperties', {}).items():
        pattern_properties.append((self.GetString(pattern),
            self.GenerateAndCollectID(subschema, pattern)));

      begin = len(self.property_nodes)
      self.property_nodes += properties
      end = len(self.property_nodes)
      self.property_nodes += pattern_properties
      pattern_end = len(self.property_nodes)

      if index == 0:
        self.root_properties_begin = begin
        self.root_properties_end = end

      extra = len(self.properties_nodes)
      self.properties_nodes.append((begin, end, pattern_end,
          additionalProperties, name))

      # Set the right data at |index| now.
      self.schema_nodes[index] = ('TYPE_DICTIONARY', extra, name)
      return index
    else:
      assert False

  def GenerateAndCollectID(self, schema, name):
    """A wrapper of Generate(), will take the return value, check and add 'id'
    attribute to self.id_map. The wrapper needs to be used for every call to
    Generate().
    """
    index = self.Generate(schema, name)
    if not schema.has_key('id'):
      return index
    id_str = schema['id']
    if self.id_map.has_key(id_str):
      raise RuntimeError('Duplicated id: ' + id_str)
    self.id_map[id_str] = index
    return index

  def Write(self, f):
    """Writes the generated structs to the given file.

    |f| an open file to write to."""
    f.write('const internal::SchemaNode kSchemas[] = {\n'
            '//  Type                          Extra\n')
    for type, extra, comment in self.schema_nodes:
      type += ','
      f.write('  { base::Value::%-18s %3d },  // %s\n' % (type, extra, comment))
    f.write('};\n\n')

    if self.property_nodes:
      f.write('const internal::PropertyNode kPropertyNodes[] = {\n'
              '//  Property                                          #Schema\n')
      for key, schema in self.property_nodes:
        key += ','
        f.write('  { %-50s %6d },\n' % (key, schema))
      f.write('};\n\n')

    if self.properties_nodes:
      f.write('const internal::PropertiesNode kProperties[] = {\n'
              '//  Begin    End  PatternEnd Additional Properties\n')
      for node in self.properties_nodes:
        f.write('  { %5d, %5d, %10d, %5d },  // %s\n' % node)
      f.write('};\n\n')

    if self.restriction_nodes:
      f.write('const internal::RestrictionNode kRestrictionNodes[] = {\n')
      f.write('//   FIRST, SECOND\n')
      for first, second in self.restriction_nodes:
        f.write('  {{ %-8s %4s}},\n' % (first + ',', second))
      f.write('};\n\n')

    if self.int_enums:
      f.write('const int kIntegerEnumerations[] = {\n')
      for possible_values in self.int_enums:
        f.write('  %d,\n' % possible_values)
      f.write('};\n\n')

    if self.string_enums:
      f.write('const char* kStringEnumerations[] = {\n')
      for possible_values in self.string_enums:
        f.write('  %s,\n' % self.GetString(possible_values))
      f.write('};\n\n')

    f.write('const internal::SchemaData kChromeSchemaData = {\n'
            '  kSchemas,\n')
    f.write('  kPropertyNodes,\n' if self.property_nodes else '  NULL,\n')
    f.write('  kProperties,\n' if self.properties_nodes else '  NULL,\n')
    f.write('  kRestrictionNodes,\n' if self.restriction_nodes else '  NULL,\n')
    f.write('  kIntegerEnumerations,\n' if self.int_enums else '  NULL,\n')
    f.write('  kStringEnumerations,\n' if self.string_enums else '  NULL,\n')
    f.write('};\n\n')

  def GetByID(self, id_str):
    if not isinstance(id_str, types.StringTypes):
      return id_str
    if not self.id_map.has_key(id_str):
      raise RuntimeError('Invalid $ref: ' + id_str)
    return self.id_map[id_str]

  def ResolveID(self, index, params):
    return params[:index] + (self.GetByID(params[index]),) + params[index + 1:]

  def ResolveReferences(self):
    """Resolve reference mapping, required to be called after Generate()

    After calling Generate(), the type of indices used in schema structures
    might be either int or string. An int type suggests that it's a resolved
    index, but for string type it's unresolved. Resolving a reference is as
    simple as looking up for corresponding ID in self.id_map, and replace the
    old index with the mapped index.
    """
    self.schema_nodes = map(partial(self.ResolveID, 1), self.schema_nodes)
    self.property_nodes = map(partial(self.ResolveID, 1), self.property_nodes)
    self.properties_nodes = map(partial(self.ResolveID, 3),
        self.properties_nodes)

def _WritePolicyConstantSource(policies, os, f, riskTags):
  f.write('#include "policy/policy_constants.h"\n'
          '\n'
          '#include <algorithm>\n'
          '#include <climits>\n'
          '\n'
          '#include "base/logging.h"\n'
          '#include "policy/risk_tag.h"\n'
          '#include "components/policy/core/common/policy_types.h"\n'
          '#include "components/policy/core/common/schema_internal.h"\n'
          '\n'
          'namespace policy {\n'
          '\n')

  # Generate the Chrome schema.
  chrome_schema = {
    'type': 'object',
    'properties': {},
  }
  shared_strings = {}
  for policy in policies:
    shared_strings[policy.name] = "key::k%s" % policy.name
    if policy.is_supported:
      chrome_schema['properties'][policy.name] = policy.schema

  # Note: this list must be kept in sync with the known property list of the
  # Chrome schema, so that binary searching in the PropertyNode array gets the
  # right index on this array as well. See the implementation of
  # GetChromePolicyDetails() below.
  f.write('const PolicyDetails kChromePolicyDetails[] = {\n'
          '//  is_deprecated  is_device_policy  id    max_external_data_size\n')
  for policy in policies:
    if policy.is_supported:
      f.write('  { %-14s %-16s %3s, %24s,\n'
              '    %s },\n' % (
                  'true,' if policy.is_deprecated else 'false,',
                  'true,' if policy.is_device_only else 'false,',
                  policy.id,
                  policy.max_size,
                  riskTags.ToInitString(policy.tags)))
  f.write('};\n\n')

  schema_generator = SchemaNodesGenerator(shared_strings)
  schema_generator.GenerateAndCollectID(chrome_schema, 'root node')
  schema_generator.ResolveReferences()
  schema_generator.Write(f)

  f.write('\n'
          'namespace {\n')

  f.write('bool CompareKeys(const internal::PropertyNode& node,\n'
          '                 const std::string& key) {\n'
          '  return node.key < key;\n'
          '}\n\n')

  f.write('}  // namespace\n\n')

  if os == 'win':
    f.write('#if defined(GOOGLE_CHROME_BUILD)\n'
            'const wchar_t kRegistryChromePolicyKey[] = '
            'L"' + CHROME_POLICY_KEY + '";\n'
            '#else\n'
            'const wchar_t kRegistryChromePolicyKey[] = '
            'L"' + CHROMIUM_POLICY_KEY + '";\n'
            '#endif\n\n')

  f.write('const internal::SchemaData* GetChromeSchemaData() {\n'
          '  return &kChromeSchemaData;\n'
          '}\n\n')

  f.write('#if defined (OS_CHROMEOS)\n'
          'void SetEnterpriseUsersDefaults(PolicyMap* policy_map) {\n')

  for policy in policies:
    if policy.has_enterprise_default:
      if policy.policy_type == 'TYPE_BOOLEAN':
        creation_expression = 'new base::FundamentalValue(%s)' %\
                              ('true' if policy.enterprise_default else 'false')
      elif policy.policy_type == 'TYPE_INTEGER':
        creation_expression = 'new base::FundamentalValue(%s)' %\
                              policy.enterprise_default
      elif policy.policy_type == 'TYPE_STRING':
        creation_expression = 'new base::StringValue("%s")' %\
                              policy.enterprise_default
      else:
        raise RuntimeError('Type %s of policy %s is not supported at '
                           'enterprise defaults' % (policy.policy_type,
                                                    policy.name))
      f.write('  if (!policy_map->Get(key::k%s)) {\n'
              '    policy_map->Set(key::k%s,\n'
              '                    POLICY_LEVEL_MANDATORY,\n'
              '                    POLICY_SCOPE_USER,\n'
              '                    POLICY_SOURCE_ENTERPRISE_DEFAULT,\n'
              '                    %s,\n'
              '                    NULL);\n'
              '  }\n' % (policy.name, policy.name, creation_expression))

  f.write('}\n'
          '#endif\n\n')

  f.write('const PolicyDetails* GetChromePolicyDetails('
              'const std::string& policy) {\n'
          '  // First index in kPropertyNodes of the Chrome policies.\n'
          '  static const int begin_index = %s;\n'
          '  // One-past-the-end of the Chrome policies in kPropertyNodes.\n'
          '  static const int end_index = %s;\n' %
          (schema_generator.root_properties_begin,
           schema_generator.root_properties_end))
  f.write('  const internal::PropertyNode* begin =\n'
          '      kPropertyNodes + begin_index;\n'
          '  const internal::PropertyNode* end = kPropertyNodes + end_index;\n'
          '  const internal::PropertyNode* it =\n'
          '      std::lower_bound(begin, end, policy, CompareKeys);\n'
          '  if (it == end || it->key != policy)\n'
          '    return NULL;\n'
          '  // This relies on kPropertyNodes from begin_index to end_index\n'
          '  // having exactly the same policies (and in the same order) as\n'
          '  // kChromePolicyDetails, so that binary searching on the first\n'
          '  // gets the same results as a binary search on the second would.\n'
          '  // However, kPropertyNodes has the policy names and\n'
          '  // kChromePolicyDetails doesn\'t, so we obtain the index into\n'
          '  // the second array by searching the first to avoid duplicating\n'
          '  // the policy name pointers.\n'
          '  // Offsetting |it| from |begin| here obtains the index we\'re\n'
          '  // looking for.\n'
          '  size_t index = it - begin;\n'
          '  CHECK_LT(index, arraysize(kChromePolicyDetails));\n'
          '  return kChromePolicyDetails + index;\n'
          '}\n\n')

  f.write('namespace key {\n\n')
  for policy in policies:
    # TODO(joaodasilva): Include only supported policies in
    # configuration_policy_handler.cc and configuration_policy_handler_list.cc
    # so that these names can be conditional on 'policy.is_supported'.
    # http://crbug.com/223616
    f.write('const char k{name}[] = "{name}";\n'.format(name=policy.name))
  f.write('\n}  // namespace key\n\n'
          '}  // namespace policy\n')


#------------------ policy risk tag header ------------------------#

class RiskTags(object):
  '''Generates files and strings to translate the parsed risk tags.'''
  # TODO(fhorschig|tnagel): Add, Check & Generate translation descriptions.

  def __init__(self, template_file_contents):
    self.max_tags = None
    self.enum_for_tag = OrderedDict()  # Ordered by severity as stated in JSON.
    self._ReadRiskTagMetaData(template_file_contents)

  def GenerateEnum(self):
    values = ['  ' + self.enum_for_tag[tag] for tag in self.enum_for_tag]
    values.append('  RISK_TAG_COUNT')
    values.append('  RISK_TAG_NONE')
    enum_text = 'enum RiskTag {\n'
    enum_text +=',\n'.join(values) + '\n};\n'
    return enum_text

  def GetMaxTags(self):
    return str(self.max_tags)

  def GetValidTags(self):
    return [tag for tag in self.enum_for_tag]

  def ToInitString(self, tags):
    all_tags = [self._ToEnum(tag) for tag in tags]
    all_tags += ["RISK_TAG_NONE" for missing in range(len(tags), self.max_tags)]
    str_tags = "{ " + ", ".join(all_tags) + " }"
    return "\n    ".join(textwrap.wrap(str_tags, 69))

  def ComputeMaxTags(self, policies):
    self.max_tags = 0
    for policy in policies:
      if not policy.is_supported or policy.tags == None:
        continue;
      self.max_tags = max(len(policy.tags), self.max_tags)

  def _ToEnum(self, tag):
    if tag in self.enum_for_tag:
      return self.enum_for_tag[tag]
    raise RuntimeError('Invalid Tag:' + tag + '!\n'
                       'Chose a valid tag from \'risk_tag_definitions\' (a '
                       'subproperty of root in policy_templates.json)!')

  def _ReadRiskTagMetaData(self, template_file_contents):
    for tag in template_file_contents['risk_tag_definitions']:
      if tag.get('name', None) == None:
        raise RuntimeError('Tag in \'risk_tag_definitions\' without '
                           'description found!')
      if tag.get('description', None) == None:
        raise RuntimeError('Tag ' + tag['name'] + ' has no description!')
      if tag.get('user-description', None) == None:
        raise RuntimeError('Tag ' + tag['name'] + ' has no user-description!')
      self.enum_for_tag[tag['name']] = "RISK_TAG_" + \
                                       tag['name'].replace("-","_").upper()

def _WritePolicyRiskTagHeader(policies, os, f, riskTags):
  f.write('#ifndef CHROME_COMMON_POLICY_RISK_TAG_H_\n'
          '#define CHROME_COMMON_POLICY_RISK_TAG_H_\n'
          '\n'
          '#include <stddef.h>\n'
          '\n'
          'namespace policy {\n'
          '\n' + \
          '// The tag of a policy indicates which impact a policy can have on\n'
          '// a user\'s privacy and/or security. Ordered descending by \n'
          '// impact.\n'
          '// The explanation of the single tags is stated in\n'
          '// policy_templates.json within the \'risk_tag_definitions\' tag.'
          '\n' + riskTags.GenerateEnum() + '\n'
          '// This constant describes how many risk tags were used by the\n'
          '// policy which uses the most risk tags. \n'
          'const size_t kMaxRiskTagCount = ' + \
                riskTags.GetMaxTags() + ';\n'
          '\n'
          '}  // namespace policy\n'
          '\n'
          '#endif  // CHROME_COMMON_POLICY_RISK_TAG_H_'
          '\n')

#------------------ policy protobufs --------------------------------#

CHROME_SETTINGS_PROTO_HEAD = '''
syntax = "proto2";

option optimize_for = LITE_RUNTIME;

package enterprise_management;

// For StringList and PolicyOptions.
import "cloud_policy.proto";

'''


CLOUD_POLICY_PROTO_HEAD = '''
syntax = "proto2";

option optimize_for = LITE_RUNTIME;

package enterprise_management;

message StringList {
  repeated string entries = 1;
}

message PolicyOptions {
  enum PolicyMode {
    // The given settings are applied regardless of user choice.
    MANDATORY = 0;
    // The user may choose to override the given settings.
    RECOMMENDED = 1;
    // No policy value is present and the policy should be ignored.
    UNSET = 2;
  }
  optional PolicyMode mode = 1 [default = MANDATORY];
}

message BooleanPolicyProto {
  optional PolicyOptions policy_options = 1;
  optional bool value = 2;
}

message IntegerPolicyProto {
  optional PolicyOptions policy_options = 1;
  optional int64 value = 2;
}

message StringPolicyProto {
  optional PolicyOptions policy_options = 1;
  optional string value = 2;
}

message StringListPolicyProto {
  optional PolicyOptions policy_options = 1;
  optional StringList value = 2;
}

'''


# Field IDs [1..RESERVED_IDS] will not be used in the wrapping protobuf.
RESERVED_IDS = 2


def _WritePolicyProto(f, policy, fields):
  _OutputComment(f, policy.caption + '\n\n' + policy.desc)
  if policy.items is not None:
    _OutputComment(f, '\nValid values:')
    for item in policy.items:
      _OutputComment(f, '  %s: %s' % (str(item.value), item.caption))
  if policy.policy_type == 'TYPE_DICTIONARY':
    _OutputComment(f, '\nValue schema:\n%s' %
                   json.dumps(policy.schema, sort_keys=True, indent=4,
                              separators=(',', ': ')))
  _OutputComment(f, '\nSupported on: %s' % ', '.join(policy.platforms))
  if policy.can_be_recommended and not policy.can_be_mandatory:
    _OutputComment(f, '\nNote: this policy must have a RECOMMENDED ' +\
                      'PolicyMode set in PolicyOptions.')
  f.write('message %sProto {\n' % policy.name)
  f.write('  optional PolicyOptions policy_options = 1;\n')
  f.write('  optional %s %s = 2;\n' % (policy.protobuf_type, policy.name))
  f.write('}\n\n')
  fields += [ '  optional %sProto %s = %s;\n' %
              (policy.name, policy.name, policy.id + RESERVED_IDS) ]


def _WriteChromeSettingsProtobuf(policies, os, f, riskTags):
  f.write(CHROME_SETTINGS_PROTO_HEAD)

  fields = []
  f.write('// PBs for individual settings.\n\n')
  for policy in policies:
    # Note: This protobuf also gets the unsupported policies, since it's an
    # exhaustive list of all the supported user policies on any platform.
    if not policy.is_device_only:
      _WritePolicyProto(f, policy, fields)

  f.write('// --------------------------------------------------\n'
          '// Big wrapper PB containing the above groups.\n\n'
          'message ChromeSettingsProto {\n')
  f.write(''.join(fields))
  f.write('}\n\n')


def _WriteCloudPolicyProtobuf(policies, os, f, riskTags):
  f.write(CLOUD_POLICY_PROTO_HEAD)
  f.write('message CloudPolicySettings {\n')
  for policy in policies:
    if policy.is_supported and not policy.is_device_only:
      f.write('  optional %sPolicyProto %s = %s;\n' %
              (policy.policy_protobuf_type, policy.name,
               policy.id + RESERVED_IDS))
  f.write('}\n\n')


#------------------ protobuf decoder -------------------------------#

CPP_HEAD = '''
#include <limits>
#include <string>

#include "base/callback.h"
#include "base/json/json_reader.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/values.h"
#include "components/policy/core/common/cloud/cloud_external_data_manager.h"
#include "components/policy/core/common/external_data_fetcher.h"
#include "components/policy/core/common/policy_map.h"
#include "components/policy/core/common/policy_types.h"
#include "policy/policy_constants.h"
#include "policy/proto/cloud_policy.pb.h"

using google::protobuf::RepeatedPtrField;

namespace policy {

namespace em = enterprise_management;

base::Value* DecodeIntegerValue(google::protobuf::int64 value) {
  if (value < std::numeric_limits<int>::min() ||
      value > std::numeric_limits<int>::max()) {
    LOG(WARNING) << "Integer value " << value
                 << " out of numeric limits, ignoring.";
    return nullptr;
  }

  return new base::FundamentalValue(static_cast<int>(value));
}

base::ListValue* DecodeStringList(const em::StringList& string_list) {
  base::ListValue* list_value = new base::ListValue;
  RepeatedPtrField<std::string>::const_iterator entry;
  for (entry = string_list.entries().begin();
       entry != string_list.entries().end(); ++entry) {
    list_value->AppendString(*entry);
  }
  return list_value;
}

base::Value* DecodeJson(const std::string& json) {
  scoped_ptr<base::Value> root =
      base::JSONReader::Read(json, base::JSON_ALLOW_TRAILING_COMMAS);

  if (!root)
    LOG(WARNING) << "Invalid JSON string, ignoring: " << json;

  // Accept any Value type that parsed as JSON, and leave it to the handler to
  // convert and check the concrete type.
  return root.release();
}

void DecodePolicy(const em::CloudPolicySettings& policy,
                  base::WeakPtr<CloudExternalDataManager> external_data_manager,
                  PolicyMap* map) {
'''


CPP_FOOT = '''}

}  // namespace policy
'''


def _CreateValue(type, arg):
  if type == 'TYPE_BOOLEAN':
    return 'new base::FundamentalValue(%s)' % arg
  elif type == 'TYPE_INTEGER':
    return 'DecodeIntegerValue(%s)' % arg
  elif type == 'TYPE_STRING':
    return 'new base::StringValue(%s)' % arg
  elif type == 'TYPE_LIST':
    return 'DecodeStringList(%s)' % arg
  elif type == 'TYPE_DICTIONARY' or type == 'TYPE_EXTERNAL':
    return 'DecodeJson(%s)' % arg
  else:
    raise NotImplementedError('Unknown type %s' % type)


def _CreateExternalDataFetcher(type, name):
  if type == 'TYPE_EXTERNAL':
    return 'new ExternalDataFetcher(external_data_manager, key::k%s)' % name
  return 'NULL'


def _WritePolicyCode(f, policy):
  membername = policy.name.lower()
  proto_type = '%sPolicyProto' % policy.policy_protobuf_type
  f.write('  if (policy.has_%s()) {\n' % membername)
  f.write('    const em::%s& policy_proto = policy.%s();\n' %
          (proto_type, membername))
  f.write('    if (policy_proto.has_value()) {\n')
  f.write('      PolicyLevel level = POLICY_LEVEL_MANDATORY;\n'
          '      bool do_set = true;\n'
          '      if (policy_proto.has_policy_options()) {\n'
          '        do_set = false;\n'
          '        switch(policy_proto.policy_options().mode()) {\n'
          '          case em::PolicyOptions::MANDATORY:\n'
          '            do_set = true;\n'
          '            level = POLICY_LEVEL_MANDATORY;\n'
          '            break;\n'
          '          case em::PolicyOptions::RECOMMENDED:\n'
          '            do_set = true;\n'
          '            level = POLICY_LEVEL_RECOMMENDED;\n'
          '            break;\n'
          '          case em::PolicyOptions::UNSET:\n'
          '            break;\n'
          '        }\n'
          '      }\n'
          '      if (do_set) {\n')
  f.write('        base::Value* value = %s;\n' %
          (_CreateValue(policy.policy_type, 'policy_proto.value()')))
  # TODO(bartfab): |value| == NULL indicates that the policy value could not be
  # parsed successfully. Surface such errors in the UI.
  f.write('        if (value) {\n')
  f.write('          ExternalDataFetcher* external_data_fetcher = %s;\n' %
          _CreateExternalDataFetcher(policy.policy_type, policy.name))
  f.write('          map->Set(key::k%s, \n' % policy.name)
  f.write('                   level, \n'
          '                   POLICY_SCOPE_USER, \n'
          '                   POLICY_SOURCE_CLOUD, \n'
          '                   value, \n'
          '                   external_data_fetcher);\n'
          '        }\n'
          '      }\n'
          '    }\n'
          '  }\n')


def _WriteCloudPolicyDecoder(policies, os, f, riskTags):
  f.write(CPP_HEAD)
  for policy in policies:
    if policy.is_supported and not policy.is_device_only:
      _WritePolicyCode(f, policy)
  f.write(CPP_FOOT)


def _WriteAppRestrictions(policies, os, f, riskTags):

  def WriteRestrictionCommon(key):
    f.write('    <restriction\n'
            '        android:key="%s"\n' % key)
    f.write('        android:title="@string/%sTitle"\n' % key)
    f.write('        android:description="@string/%sDesc"\n' % key)

  def WriteItemsDefinition(key):
    f.write('        android:entries="@array/%sEntries"\n' % key)
    f.write('        android:entryValues="@array/%sValues"\n' % key)

  def WriteAppRestriction(policy):
    policy_name = policy.name
    WriteRestrictionCommon(policy_name)

    if policy.items is not None:
      WriteItemsDefinition(policy_name)

    f.write('        android:restrictionType="%s"/>' % policy.restriction_type)
    f.write('\n\n')

  # _WriteAppRestrictions body
  f.write('<restrictions xmlns:android="'
          'http://schemas.android.com/apk/res/android">\n\n')
  for policy in policies:
    if policy.is_supported and policy.restriction_type != 'invalid':
      WriteAppRestriction(policy)
  f.write('</restrictions>')

if __name__ == '__main__':
  sys.exit(main())